1. Field of the Invention
This invention relates to a mounting device, and more particularly to a mounting device that is disposed within a mounting hole in a horizontal plate (e.g., a ceiling) for mounting an electronic device (e.g., a speaker) to the plate.
2. Description of the Related Art
Referring to FIGS. 1, 2, and 3, a conventional speaker assembly disclosed in Taiwanese Patent Number M338520 includes a speaker 11, an annular frame 12 attached to a bottom end of the speaker 11, and two clamping devices 13. Each of the clamping devices 13 includes a connecting member 14 mounted fixedly to a corresponding side surface 111 of the speaker 11, a pivotable clamping member 15, and a movable member 16. A first bolt 17 extends through a first hole 151 in the pivotable member 15, and engages a threaded hole 141 in the connecting member 14 such that the pivotable member 15 is rotatable about the first bolt 17. A second bolt 17′ extends through a horizontal hole 161 in the movable member 16 and a second hole 152 in the pivotable member 15. An adjustment bolt 18 engages a vertical threaded hole 162 in the movable member 16. A clearance is formed between the second bolt 17′ and the movable member 16 so that, when the movable member 16 moves vertically on the adjustment bolt 18, the pivotable member 15 can rotate about the first bolt 17.
When it is desired to mount the conventional speaker assembly to a ceiling 10, referring to FIG. 2, the pivotable members 15 are first pivoted to vertical positions to allow the speaker 11 and the pivotable members 15 to be moved through a mounting hole 101 in the ceiling 10. Next, the user rotates the adjustment bolts 18 one at a time with one hand to move the movable members 16 downwardly while supporting the annular frame 12 with the other hand. Hence, the pivotable members 15 are pivoted respectively and downwardly about the first bolts 17 until clamping portions 153 of the pivotable members 15 come into contact with a top surface of the ceiling 10, thereby clamping the ceiling 10 between the annular frame 12 and the clamping plate portions 153. As such, it is difficult to mount the conventional speaker assembly to the ceiling 10.